Pneumatic means for mounting carriages on wheels.



H. MERCIER.. PNEuMATlc MEANS FoR'MouNTlNG cARmAGEs'oN WHEELS.

Patent@ Apr. 18,1916.

' To all whmi't'nay concern J.

sTTEs PATENT oFFICE g NEnMA'rIc Mmnsron MOUNTING CARRIAGES oN urinarias.'A

Be it known'thatl, HENiii Mnu'cwu, citi Vzenl of the French Republic, residing at Paris, Department of the Seine, in France, i have mventedy certain Vnew and usefuly lmprovements in Pneumatic Means for Mounts ing Carriages on ljVheels; and I-'do hereby `declare-'the vfollowing tobe full, clear, and

. exact description of the invention, such as will yenable'others skilled in the artfto which it apprtains tomakeand usethe same.

This-invention relates to pneumatic sus-l pension devicesA for vehicles of the kmd com- -prlsing a piston moving withln a cylinder havingY ajleakage aperture andA fed with controlled fvalve,` anfa-uxiliary airchamber l preis to, .reine n being:` Vprovided coninnmicating.-fivith the.'` cylinder through a ksmall.

openedV and olosedgbyllthe piston. 1

A Thesefdeviceswere defective in that-'they very-largequantityof cour au ,'and" the present invention --seeks the prior devicesl y A According to 'fthe present invention, the admission of air is controlled by a springclosefdvalve which is opened by the piston only after the latter has closedthe passage leading f'ffrmfthe. cylinder to the'auxiliary airicharnbeiz Oiving to .this arrangement, alr 1s -not'admitted directly from the airadmissiQnE-valve "to the auxiliary chamber.

I .the interior of .the piston, so-that the hollow Another'fea'ture 'ofthe inventionconsists in making the pistony hollowand `providing Va small hole leading from thecylinder to piston acts as bei'. -V In order to prevent loss of air through the'leak-hole when the'piston moves'downa second auxiliary air-cham- Wardlyj. only for amoinenhas when the wheel passes a hole inthe road, a vretardingv apparatus isprOvided, comprising a small cylinder'fr having a. spring-.pressed piston Which'mustcb'e pushed a certain distance beoreair can yleak'iiito the atmosphere. Thus unlessthe leak-hole is uncovered for an appreciable time no loss of'air lcan take place.

In `the accompanyingdrawings vgiven by way of example z-Figure 1 shows in section a construction of the suspdnsion `device ziccording! to 'this invention: F ig. 2 shows ,a section oLthe sma'illcylinder retarding the `escape of air'; F ig. 3 shows in section a, sus! v Specification of Ilettersfatent. Patented 'f Appucatioared Jane 11. 19'14p serauwa'fimosj `cylinder L-ilintendedr to receive thei piston,

1 small 4porty A3l arranged, vin the-constlfiictiol' i cylinder.' Vthe wall of the cylinden are K A [two leak-holes-l orcompressed ain through an' automatically ihole fivhich is( mouth of the cylinder,".saidcollarpbeingfse s' cured to thecylinder' by studsand nuts,-an l forming a guide for the. piston. Said collar dy-tliis and otherdisadvantages rof l cylinder A. It comprises three main parts cover Bf, the latter 'troduced or projected against the coverfo `this grooveto. a point opposite theprt A# oil escapes throughthe holes Bfalnd/falls `back again 'into `the'interiorof thefpiistonfr -hom which 1t is raised g again during` th lected 'at the bottom" of .the pistonLf Th" of the cylinder, the leathersandjhe.

'thedash-poti chamber.4 The leatliers'Bf pensioniin which, rin addition "to ,theu'sualf air inlet-valve, a supplementary' valve" is used; and Fig.A l vshows amoiolifiedfV con# struction in which the twovli'lvesshow-n in" Fig', l are combined in a fsingle valve.` v i A is the cast iron' bod)7 Whii'lris seculfed"r lo the 'chassis of the vehicle 1?(not 'sl1oivn),.`

The body comprises two inain'partS, the

communicateswith the cylindei'tlu'ough a" I illustrated, `at 20min. 'from the coverq'f th A7 isan annular hrass collarc'losingfthef discharge g' jorifices i FA;4 f

also limits the stroke'of thepiston'.l B is the hollow piston. traveling;inltlie the body. B1, theleathers- B2, and'thepiston securing. the A leatherst the'piston by means'of screws;- y

4 Owing to the reqiiirelnentsot. lubrication.. and alsoin order to `insure-free ci culati'ol of the compressed airdriving'th Athe upperfa'ce of the cover- '1533 fgrooved-- in an annularmanner so-as vto preventits adhesion to the coveri of'` the', cylinder These grooves are'sho'wngat Blfin-FiggLr The said face is also provided" with a 4circu larJ groove 1 5* intended to collectjtheoilin the cylinder, anda small hole B leads'from for .a purpose ,hereinafter described-l The .violent:oscillations of the piston yaniiifunde the action of ushesj of an'. Thisinslu contlnuous clrculationpof the 'oilsuppl .g c ollar thus receive automaticallythe -quan tity .of oilrequired for satisfactoryopera tion, andvery little oil'is carrie .awaylinto' pressed against the wall of Vthe cylinder; l

a compressed helical spring BG previously placed on a split. ring B7 (lig. l.) This thrust oE the roller BJ ot the piston. The movement oic the piston is transmitted amplified b v thc lever to the hanger C2 which acts on the end ot' the ordinary laminated or leaf spring of the car.

y the piston has descended to an extent corresponding to the closing of the valve, that is ted becomes too great. It 'as hitherto con' sidered obvious that the leak-hole A* had to he made of very small cross-section to afford passage to a small quantity of fiuid, as it was arrangement is necessary for insuring a to say .20 mn'nin the 'apparatus illustrated, proper joint of the leathers. v the port A3 is uncovered at the same mo- Between the piston' and the cylinder is ment; and all the parts of the apparatus are 70 arranged an annular cylindrical space B12 then in open communication with each other freely communicating with theI atmosphere and also filled with air at 'the pressure necesthrougli an a'irhole BS (Fig. l). When the sary for balancing the weight of the car ata iston'is lowered. this air hole is at a certain standstill. In these conditions, the device is moment covered by the collar A7,@ Therereadyito work as soon as the car 1 s started. 75 after the said annular space is closed. the air In fact, as soon as there are -any vibrations, contained in the same compressed and the rod of the4 valve is struck by the projecforms an air cushion for avoiding shock of, tion B1 of the piston. This results in a s ethe piston against the ring, at the bottom of ries of newy admissions of compressedI air, 1'5 its stroke. The same appliesv when the-.cylwhich takes lplace instantaneously -at each 80 iiider rises to the top of its stroke, the air blow of the projection B1" against the rod of forced back by the rising n'ioveine'nt of the the valve. These additional admissions of piston, can no Alonger freely escape into the compressed flliid gradually result in moving dash-pot auxiliary air-chamber as soon as the piston' away from the cover of the cylthe upper face ot the piston cover B3 covers indcr to a greater extent than it was ii1 the 85 the port A3, for at that moment the coni' equilibrium position hereinbctore described pressed air at tlie`upper portion of the cylfor the cai' at standstill. The blows then inder is in communication with'the port Al become more and more rare, andl cease com-. only through the small hole B and with the pletely Jtor a given state of the road. rThe interior of the piston only through the holes device thus finds. a new position of equilib- 90 These holesythe cross-sections of which rium. This position of equilibrium does not. are very small, cannot discharge sufli'ciently however, correspond to the position of thev quickly the air'inclosed between the piston leak'-hole A4.' .It de ends exclusivelyon the and the cover of the cylinders, yand the said state of the road. ghe worse the road, the

aii" forms a cushion and prevents any shockl more the suspension is inflated, and the bet- 95` of the piston against the cover of the 'cylin-v terlit adapts itself to the requirements of der, at the top oits stroke. The piston is the moment. The yleak-hole A* moreover connected to thc wlieel of the vehicle by fixes a limit- .to the said inflation, and it enmeans of a roller B rotating on a .pin seables the device. as soon as the .road imcured to the walls ot' the piston, and a lever proves, to return to a less inflated condition, 10( C which rests on thesocket A and can move adequate for the reduced movements of the in the vertical plane by rotating about the axle and. of the piston.

pin of the said socket. The Asaid level' is The leak-hole A* becomes also operative provided with a thrust block C1 having a `it`for any reason other than that` of the hardened surface. and adapted to take the state of the road. the quantity of air admitfrequently uncovered when the wheels passed 119 over holes in the road, and at that moment it was advisable not to allow too large a quantity of fluid to escape. Experience has proved. however. that holes. even small ones. opening' intoxtheatmosphere discharge fre 115 quently an excessive quantity of fiuidvwhile the same small holes present the disadvan-r tage of becoi'ninggfrequently choked. Fig.

:2 shows tliedevice used for 'obviating this double drawback. To that end. the leak-k 120 hole A4, provided with a cross-section amply sufficient to avoid choking, communicates with a small cylinder l provided with a pis-V ton 2 and with a secondary air hole orleakage hole 3 of lai-gr cross-section. A spring 125 l always returns the piston to the bottom of its stroke. The result of this arrangement is that the uncovering tor a very short time of the leak-hole does not result in a los of air, as the piston of the small cylinder In addition to the air-hole A* which is uncovered .by the leathers'when the' piston is lowered, there is asecond air-hole A5 which acts as an auxiliary safety outlet.

-Compressed air is admitted through the air-inlet valve lll,l lVlien the piston at the top of itsstrokc. the valve D1 is lifted (in the type described in Fig. l. the said travel is L10 mm.).` Compressed air passes around the loosely fitting valve IP. then along the rod of the valve. which is grooved to that end, spreads in the cavity of the piston. passes through the holes B1 and exercises its pressure on the upper face ot the piston. Under the action oi the said pressure, the piston is lowered. the valve. pushed b v the spring D3. slides .in the guide plug D2 in accordance with the movement ot' the piston. The valve D closes when the face D1'1 comes into contact with the seating D111 When 'i other mechanical part.

thj-akage hole in time. c

cany ou ino-ve suiiicientlyyquickly to uncover ii is introduced through the' iioie'afinie the'gijoove-Bf and escapes through the conl It collects at .rest onl the bottom froth landfdrawn inby the charges of .air

resulting om sudden descents of the piston,

to the uppe PQI'tion rof the cylinder whencey it reaches the friction, surfaces in orderl to collect afterward again in the groove B* and fall back tothe-bottom of the piston. Continuous' automatic lubricationk is thus produced without theintervention' of any In order to diminish the frequency of the fluctuations, valves "may, be `provided as shown in Fide. 3'and L which revent loweri ingof pressure in the cylinder due Vto the leaka-ges of the'device by introducing continually a very small quantity of fluid. In addition t0 ,thevusual .air inlet valve .D1 supplied from the compressedeair ductA D and controlled byaspriiig D3 andv arranged in the interior of the'piston B moving in the cylinder 'A, there is arrangedfan additional valve 20, throttled by the lhelical grooves 21, ated by a the piston is at the top of its stroke, the

valve 20 is-'pushed back by the bosslblo'to a A' heirhtcorresponding to the'distance separating the eiid of the stamped out leathers B2 from. the leak-hole A4. `In these conditions, tlie valve 2O .supplies airmcontinuously until the piston B VLuncovers the leak-hole andthe horizontal position of the chassis is an excessively rapid A4. .The ysuspensions thus assume. iii the position of rest, an equal degree of inflation,

graduallyrestablished. In order to avoidl the leak-hole Ajthe' latter is provided with a screwhaving a retardiiig groove 19. l The -auxiliaryV leak-hole A5 always discharges freely into the atmosphere.

Fi l'shows'an arrangementin which the two valves 20 and D1 of 1 are-combined. The spindle of this combinedvalve 21 is provided witha'rectilinear groove 22 of a crosssection and length calculated so. asvto-admit air quickly ,into the chamber of the piston,v as long as the latter has not uncovered the'l auxiliary Y, air-chamber. The; admission of air is subsequently insured by a helical,v groove 23 rendering the discharge slower as 1. In pneumatic suspensionmechanism for,

vehicles., the combination of a cylinder, a piston operating` therein, 4`first 'and second auxilpistom During'` the running it is.

yclosed by a spring als' and operf. boss4 b1 'in the` piston'B. When l tor vehicles, the combination of a cylinder; a

,outlet of a-ir through yspace .above the piston, an auxiliary cham` ,c leading lfromlthe cylinder to said auxiliary chamber and so disposed asVA iary chambers, valve mechanism operated 'by f relative movements between the cylinder and 4 ythe piston for admitting compressed fluid l to the second auxiliary chamber, said secondt i' i auxiliary chamber beingin permanent vcoin'-y iuunication with vthe space betiveen'tlie head* of the piston and the end of tliec vliiidei'f,

and afpassage leadinglfrom rthev cylinder toy -1 the first auxiliary chamber and so positioned as to place said space iii communication a hollow piston lope-rating therein, valve c l" L with the first auxiliary chamber y after pre-"1 mechanism operated by movementso the" piston for admitting compressed luidto the interior of the piston, a restricted passage placing the "S5-. interior of the piston in -j communication with thespace above the pis-fn ton, an auxiliary chamber and a passage leadingA from the cylinder to said auxiliary .chamber and so 'disposed asto'establishfcomvmunicationbetween said space above thev j piston and the auxiliary chamber 'after a predetermined movement Aof the piston, said f valve mechanism being `.arranged to close x when'such communication is established.

3..In pneumatic Asuspension mechanism'.- i

piston operating therein, means comprising a valve actuated' by relative movementsbe;-

a discharge orifice in thewall of the cyl-.

inder, a relatively small'ylin'dei-into which said orifice discharges, and a spring-pressed"- piston yieldingly resisting the discharge of fluid from said relatively small cylinder.

' 4. In pneumatic suspension` mechanism I' for vehicles,l the combination of .a cylinder.`

a piston operating therein, means comprise.

ing a valve to admit compressed Huid to the ber. a passage to establish communication between the space above the piston and said auxiliary chamber c `after predetermined `movement 0f vhe pis f ton', a discharge oriiceloc'ated inthe cylinr'-,` i

der ivallat apoint below saidpassage, and i auxiliary fluid-supplying means' designed "to continue the admission of compressed fluid to the space above .thepiston until the piston uncovers said discharge orifice.`

5. In pneumatic suspension. mechanismI for vehicles, the combination ofqa cylinder.` f

- a piston operating therein'` means compris# i ing a valve actuated by relative movementsy between the piston and cylinder 'atop admit -compressed fluid to the space abovethe fpis; f ton. an auxiliary chamber,

from the cylinder to seid auxiliary chamber v a passage leading and so disposed as to establishcommunication between the space ahove thejpistoii and-tflie'auxihai-i' chamber after pifedeteviiiiiied movement oi the piston. a discharge orifice located iii` the Cylinder wall at a'point liv'low Said pasisage, and a zQroovod vaivo stiii associated with ,Said'-vali'e to admit fhiid to the space above the piston iii ruhitively-hiige quantities iip to the time that' 10 vsaid passage is uncovered h v the piston and 

